The invention relates to a device for delivering ventilation air to the front of the cabin of a motor vehicle, this ventilation air being delivered by a delivery box of a heating, ventilation and/or air-conditioning unit, said device comprising at least one ventilation pipe supplying at least one air vent provided in the dashboard and connected to an outlet of said delivery box, the cross section of which is adjusted by a delivery shutter.
In general, the delivery box comprises several outlets for selectively supplying the defrosting pipes, the dashboard ventilation pipes and possibly the pipes for ventilating the lower part of the cabin. The delivery box comprises, for this purpose, distribution shutters controlled from a control panel arranged in the vehicle console or in the central part of the dashboard. The ventilation pipes in the dashboard deliver air to several air vents, particularly the central air vents and the lateral air vents. These air vents are equipped with orientable fins and with a shutter for adjusting the flow rate of the air delivered, these being controlled manually by the driver or the passenger. This shutter for adjusting the flow rate is arranged near the outlet orifice.
The cross sections of these air vents are relatively small and the ventilation air emerges at a speed in excess of 5 m/s in ventilation mode alone or in a combined ventilation/defrosting or ventilation/feet-heating mode. These high speeds cause noises.
In certain vehicles, it has already been proposed for the ventilation air to be delivered through orifices of large cross section distributed in particular on the upper face of the dashboard behind the windshield and the defrosting nozzles. The total surface areas of these orifices are calculated so that the air emerges at a speed below 5 m/s. This mode of ventilation is known as xe2x80x9cgentlexe2x80x9d as opposed to xe2x80x9cforcedxe2x80x9d ventilation in which the air leaves the vents at a speed in excess of 5 m/s.
Hybrid ventilation devices in which some of the ventilation air is delivered gently by outlets of large cross section distributed over the upper face of the dashboard and some is delivered in a forced way by air vents directed toward the cabin are also known. Each air vent has its own adjusting shutter, so as to allow the driver or the passenger to adjust the flow rate from each vent. The total flow rate of ventilation air is adjusted by a shutter on the delivery box. However, these known devices do not allow ventilation air to be delivered in forced mode only.
The object of the invention is to propose a delivery module such as mentioned in the introduction and which allows the distribution of ventilation air to be adjusted between xe2x80x9cgentlexe2x80x9d ventilation mode and xe2x80x9cforcedxe2x80x9d ventilation mode.
The object is achieved in that said ventilation pipe is formed in a delivery module which runs transversely under the upper face of the dashboard, in that said ventilation pipe splits downstream in the direction of flow of the ventilation air into at least one xe2x80x9cgentlexe2x80x9d ventilation pipe which opens onto the upper face of the dashboard via ventilation orifices of large cross section and into at least one xe2x80x9cforcedxe2x80x9d ventilation pipe which supplies at least one air vent of small cross section arranged on the dashboard facing the cabin, and in that at least one air distribution shutter is provided at the junction between the three pipes, said distribution shutter being controlled independently of the delivery shutter.
According to a first embodiment of the invention, the device comprises a single ventilation pipe arranged in the central region of the module and splitting into a single xe2x80x9cgentlexe2x80x9d ventilation pipe opening via orifices distributed transversely behind the windshield and into two lateral xe2x80x9cforcedxe2x80x9d ventilation pipes arranged symmetrically in the dashboard.
Advantageously, each lateral xe2x80x9cforcedxe2x80x9d ventilation pipe subdivides into a central duct supplying a central air vent and into a lateral duct supplying a lateral air vent.
According to a second embodiment of the invention, the device comprises two ventilation pipes arranged symmetrically in the central region of the module and which are intended to supply ventilation air to the left-hand part and the right-hand part of the cabin respectively, each of these ventilation pipes having its own air distribution shutter.
Advantageously, each ventilation pipe splits into a single lateral xe2x80x9cgentlexe2x80x9d ventilation pipe opening via orifices distributed transversely behind the windshield and into a single lateral xe2x80x9cforcedxe2x80x9d ventilation pipe.
As a preference, the lateral xe2x80x9cforcedxe2x80x9d ventilation pipe subdivides into a central duct supplying a central air vent and into a lateral duct supplying a lateral supply vent.
According to a third embodiment of the invention, the device comprises four ventilation pipes arranged transversely in the central region of the module, namely two central pipes delivering ventilation air to the lateral regions of the dashboard, and two lateral pipes delivering ventilation air to the left-hand and right-hand central regions of the dashboard respectively.
Advantageously, each ventilation pipe divides into a single xe2x80x9cgentlexe2x80x9d ventilation pipe opening via orifices distributed transversely behind the windshield and into a single xe2x80x9cforcedxe2x80x9d ventilation pipe and comprises its own air distribution shutter.
As a preference, each central ventilation pipe passes over and to the rear of the xe2x80x9cgentlexe2x80x9d ventilation pipe supplied by the adjacent lateral ventilation pipe.
The xe2x80x9cforcedxe2x80x9d ventilation pipe supplied by a central ventilation pipe is arranged above and to the rear of the xe2x80x9cgentlexe2x80x9d ventilation pipe supplied by said central ventilation pipe.
As a preference, the module further comprises a defrosting pipe arranged in the front part of said module.
The module may further comprise two lower lateral pipes for supplying the lower region of the cabin with air.